title: Usefulness of negative and weak-diffuse pattern of SDHB immunostaining in assessment of SDH mutations in paragangliomas and pheochromocytomas.
abstract: This is a confirmatory study about usefulness of SDHB and SDHA immunostaining in assessment of SDH mutations in paragangliomas and pheochromocytomas. Paraganglioma/pheochromocytoma syndrome (PGL/PCC syndrome) consists of different entities, associated with germline mutations in five different genes: SDHD, SDHAF2, SDHC, SDHA and SDHB. It has been suggested that negative immunostaining of SDHB can be taken as an indicator of the presence of a mutation in one of the five SDH genes. We have performed SDHB and SDHA immunohistochemical staining in a series of paragangliomas and pheochromocytomas from 64 patients. The patients had been previously checked for mutations in SDHD, SDHC and SDHB, but also for mutation in RET and VHL. All 14 patients with SDH mutations (9 with SDHB and 5 with SDHD mutations) exhibited negative or weak-diffuse SDHB staining pattern in tumour tissue, whereas cells of the 23 RET mutated and 8 VHL mutated tumours showed a positive SDHB immunostaining. Sixteen of the patients that did not exhibit a mutation in any gene showed positive SDHB immunostaining in tumour tissue, while only three of the patients without mutation exhibited negative staining. All patients exhibited positive pattern of SDHA immunostaining. The results confirm the value of SDHB immunohistochemical status in assessment of germline mutations in PGL/PCC syndrome.
authors.affiliation: Department of Pathology and Molecular Genetics, and Research Laboratory, Arnau de Vilanova Universitary Hospital, University of Lleida IRBLLEIDA, Lleida, Spain.
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Castelblanco
authors.forename: Maria
authors.initials: M
authors.lastname: Santacana
authors.forename: Joan
authors.initials: J
authors.lastname: Valls
authors.forename: Aguirre
authors.initials: A
authors.lastname: de Cubas
authors.forename: Alberto
authors.initials: A
authors.lastname: Cascón
authors.forename: Mercedes
authors.initials: M
authors.lastname: Robledo
authors.forename: Xavier
authors.initials: X
authors.lastname: Matias-Guiu
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000235:genetics / Q000378:metabolism*; D000328:Adult; D042963:Electron Transport Complex II / Q000235:genetics / Q000378:metabolism; D005260:Female; D018095:Germ-Line Mutation; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D010235:Paraganglioma / Q000235:genetics / Q000378:metabolism*; D010673:Pheochromocytoma / Q000235:genetics / Q000378:metabolism*; D013385:Succinate Dehydrogenase / Q000235:genetics* / Q000378:metabolism
chemical_list: D042963:Electron Transport Complex II; C511268:SDHA protein, human; C108095:SDHB protein, human; D013385:Succinate Dehydrogenase